Long-Term Debt and Lines of Credit - Long-Term Debt - Narrative (Detail) - USD ($) $ in Millions		3 Months Ended
	Aug. 11, 2015	Jul. 31, 2016	Aug. 02, 2015	Aug. 11, 2008
Debt Instrument [Line Items]
Long-term debt			$ 2.2
Unsecured senior term notes [Member]
Debt Instrument [Line Items]
Issuance of unsecured term notes				$ 11.0
Fixed interest rate				8.01%
Term of the note agreement		7 years
Required amount of principal payment installments		$ 2.2
Required debt payment frequency		Annual
Date of first required principal payment		Aug. 11, 2011
Last annual payment paid	$ 2.2
Long-term debt, fair value			$ 2.3